Seawater is a storehouse of chemicals and contains more than 73 elements in dissolved state. Coastal locations have abundant seawater whereas landlocked areas do not have seawater. Yet seawater may be required in the latter areas too for diverse purposes. Since transporting seawater is a costly and difficult proposition, many efforts have been made to constitute compositions which mimic seawater. However, these are not exact replica of seawater and in that sense they are non-standard compositions which vary from formulation to formulation. The only thing that appears to be common to all is their prohibitive cost which further limits the scope of such seawater applications in locations not blessed with a coast line.
Fresh water is what we drink and also use for agriculture. In many instances the water is severely deficient in nutritious minerals, particularly the water obtained from desalination plants. Indeed, it is unfortunate that the desalination process not only drives out sodium chloride but also essential minerals and in cases such as reverse osmosis based desalination, these are preferentially driven out making a bad situation worse. Although the problem can be mitigated through re-mineralization, many plants do not practice re-mineralisation due to the additional cost involved, particularly the high cost of the nutrient salts.
Reference may be made to the article entitled “Elemental composition of commercial sea salts” by M. J. Atkinson and C. Bingham (Journal of Aquariculture and Aquatic Sciences, 1997, Volume VIII, No. 2, Page 39-43) in which it is reported that eight different commercially available synthetic sea salt mixes were analyzed for some thirty-five elements and ions and other chemical parameters. Although the major cations and anions were within 10% of seawater in most of the salts, there were significant differences in the amounts of the minor constituents. It was found that “total CO2 varies about 20 times, B varies about 13 times from 0.36 to 4.90 mmol kg−1, phosphate concentrations vary 24 fold from extremely low values of 0.05 μmol kg−1 to moderate concentrations of 1.2 μmol kg−1, nitrate varies from 0.79 to 18.4 μmol kg−1, and most transition metals are present in substantially higher concentrations compared to normal seawater. It is therefore apparent that none of the salts studied can be assumed to be natural salt compositions mimicking a dried sea.
Reference may be made to http://web.archive.org/web/20001215070800/http:/www.animalnetwork.com/fish2/aqfm/1999/mar/features/1/default.asp, different sources of brine as listed in the following table from which artificial seawater can be produced in the solid form. Most of these compositions are silent on the essential trace elements present in seawater. Another drawback of these sources is that these products having the cited compositions are invariably expensive. They are available in a price range of 45-70 USD per 150-200 gallons of seawater which works out to a premium cost of Rs. 2/liter than that of natural sea water.
TABLE 1The Composition of Several Synthetic Seawater MixesMain ConstituentsCommercialSalinityName(ppt)NaMgCaKSrCl—SO4—BO3HCO3—CO3—Seawater354705310.3 10.2 0.09550 280.421.90Instant Ocean29.65462529.09.40.19 521230.441.90Tropic Marine32.64442468.99.10.08497 210.361.10HW Marine Mix29.40467539.010.10.15 538 280.412.10Reef Crystals28.91461 509.39.50.08 520270.650.75Red Sea Salt30.07472559.09.90.10 537 250.541.08Kent28.854605710.4 10.1 0.10 531240.542.52Coralife28.39464 6310.1 9.30.08566 151.26.32Sea Chem29.545043710.1 10.70.21 516374.90.12ppt = parts per thousand
Reference may be made to US 2005/0193956 dated: Aug. 9, 2005 Axelrod, Glen S. et al discloses a process for the preparation of a synthetic ocean salt comprising the mixing of Sodium Chloride 50-55% (wt) Magnesium Chloride 30-32% (wt) Anhydrous Sodium Sulphate 7-10% (wt) Calcium Chloride 2-4% (wt) Potassium Chloride 2-4% (wt) Sodium Bicarbonate 0.1-1% (wt) Boric Acid 0.001-0.010% (wt). The invention reports the preparation of a synthetic ocean mix from pure chemicals.
Reference may also be made to an article entitled “Guidance from Secondary Data for Re-mineralisation of RO Water” by Srivastava et al (Journal of Indian Water Works Association, January-March 2010 issue, pp. 50-52) which discusses ideal water compositions for potable purposes. The need for remineralisation of such desalinated water is evident from the article.
References may be made to an article by Gordon Sato et al (Cytotechnology (2011) 63:201-204) and many other articles in the prior art which disclose the well known use of media such as Zobell marine broth and ASNIII for culturing of marine microbes.
In view of the above there is a need for the invention of inexpensive, effective and uniform salt compositions to cater to the needs as described above.